Phenibut FAA (powder) – 50g

Phenibut is GABA with a phenyl ring attached, developed in Russia in the 1960s as an anti-anxiety and nootropic drug. It is a close structural relative of baclofen.

• Anxiety, tension and sleep (clinical use in Russia)
• GABA-B receptor pharmacology
• Calcium-channel (α2-δ) binding and pain models in rats
• Dependence and withdrawal (toxicology)

It acts mainly as a GABA-B receptor agonist. Its active R-form also binds the α2-δ subunit of voltage-dependent calcium channels - the gabapentin target - with about four times the affinity it has for GABA-B receptors.

1. Review

   Pharmacology review (CNS Drug Rev 2001)

   Describes phenibut as a GABA-mimetic acting mainly at GABA-B receptors, used in Russia to relieve tension, anxiety and fear and to improve sleep.[1]

2. Animal study

   α2-δ binding and pain models (Pharmacol Biochem Behav 2015)

   In rat brain tissue R-phenibut bound the gabapentin site on calcium channels, and in rat pain models it had gabapentin-like effects that a GABA-B blocker did not remove.[2]

3. Human · small / uncontrolled

   U.S. poison centers 2009-2019 (MMWR 2020)

   1,320 phenibut exposures were reported from all 50 states and DC; 85% of calls came from health-care facilities. Cases rose sharply over the decade, especially after 2015, when poison centers could first log phenibut by name.[3]

4. Review

   Withdrawal: systematic review (Clin Toxicol 2023)

   25 published cases of phenibut withdrawal: 44% were admitted to intensive care and 24% were intubated. Symptoms began as soon as two hours after the last use, and every published case of abrupt stopping was managed in hospital.[4]

5. Product testing

   U.S. supplement testing (Neurol Clin Pract 2021)

   Detected among unapproved drugs in U.S. cognitive-enhancement supplements; several products contained drugs their labels did not declare.[5]

• Human data are clinical experience from Russia, poison-center calls and case reports - not modern randomized trials.
• Dependence and withdrawal are documented in the sources above.
• Products on this site are sold for laboratory research only. They are not the medicines used in the trials above, and those results do not apply to research material.

1. 1.Phenibut (beta-phenyl-GABA): a tranquilizer and nootropic drugLapin I. CNS Drug Rev. 2001 Review
2. 2.R-phenibut binds to the α2-δ subunit of voltage-dependent calcium channels and exerts gabapentin-like anti-nociceptive effectsZvejniece L et al. Pharmacol Biochem Behav. 2015 Animal study
3. 3.Notes from the Field: Phenibut Exposures Reported to Poison Centers - United States, 2009-2019Graves JM et al. MMWR Morb Mortal Wkly Rep. 2020 Human · small / uncontrolled
4. 4.A systematic review of phenibut withdrawal focusing on complications, therapeutic approaches, and single substance versus polysubstance withdrawalFeldman R et al. Clin Toxicol (Phila). 2023 Review
5. 5.Five Unapproved Drugs Found in Cognitive Enhancement SupplementsCohen PA et al. Neurol Clin Pract. 2021 Product testing